Incorrect iterator++ in ModuleRtpRtcpImpl::RegisterVideoBitrateObserver

The iterator is incremented both in loop header and loop body. Should
only be incremented in header.

BUG=2727
R=mflodman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/5899004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5295 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc
index b476f2c..e58a46c 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_rtcp_impl.cc
@@ -1577,7 +1577,6 @@
         RtpRtcp* module = *it;
         if (module)
           module->RegisterVideoBitrateObserver(observer);
-        ++it;
       }
       return;
     }